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Related to Paranasal sinusitis: pansinusitis, Acute sinusitis




Sinusitis refers to an inflammation of the sinuses, airspaces within the bones of the face. Sinusitis is most often due to an infection within these spaces.


The sinuses are paired air pockets located within the bones of the face. They are:
  • the frontal sinuses; located above the eyes, in the center region of each eyebrow
  • the maxillary sinuses; located within the cheekbones, just to either side of the nose
  • the ethmoid sinuses; located between the eyes, just behind the bridge of the nose.
  • the sphenoid sinuses; Located just behind the ethmoid sinuses, and behind the eyes.
The sinuses are connected with the nose. They are lined with the same kind of skin found elsewhere within the respiratory tract. This skin has tiny little hairs projecting from it, called cilia. The cilia beat constantly, to help move the mucus produced in the sinuses into the respiratory tract. The beating cilia sweeping the mucus along the respiratory tract helps to clear the respiratory tract of any debris, or any organisms which may be present. When the lining of the sinuses is at all swollen, the swelling interferes with the normal flow of mucus. Trapped mucus can then fill the sinuses, causing an uncomfortable sensation of pressure and providing an excellent environment for the growth of infection-causing bacteria.

Causes and symptoms

Sinusitis is almost always due to an infection, although swelling from allergies can mimic the symptoms of pressure, pain, and congestion; and allergies can set the stage for a bacterial infection. Bacteria are the most common cause of sinus infection. Streptococcus pneumoniae causes about 33% of all cases, while Haemophilus influenzae causes about 25% of all cases. Sinusitis in children may be caused by Moraxella catarrhalis (20%). In people with weakened immune systems (including patients with diabetes; acquired immunodeficiency syndrome or AIDS; and patients who are taking medications which lower their immune resistance, such as cancer and transplant patients), sinusitis may be caused by fungi such as Aspergillus, Candida, or Mucorales.
Acute sinusitis usually follows some type of upper respiratory tract infection or cold. Instead of ending, the cold seems to linger on, with constant or even worsening congestion. Drainage from the nose often changes from a clear color to a thicker, yellowish-green. There may be fever. Headache and pain over the affected sinuses may occur, as well as a feeling of pressure which may worsen when the patient bends over. There may be pain in the jaw or teeth. Some children, in particular, get upset stomachs from the infected drainage going down the back of their throats, and being swallowed into their stomachs. Some patients develop a cough.
Chronic sinusitis occurs when the problem has existed for at least three months. There is rarely a fever with chronic sinusitis. Sinus pain and pressure is frequent, as is nasal congestion. Because of the nature of the swelling in the sinuses, they may not be able to drain out the nose. Drainage, therefore, drips constantly down the back of the throat, resulting in a continuously sore throat and bad breath.


Diagnosis is sometimes tricky, because the symptoms so often resemble those of an uncomplicated cold. However, sinusitis should be strongly suspected when a cold lingers beyond about a week's time.
Medical practitioners have differing levels of trust of certain basic examinations commonly conducted in the office. For example, tapping over the sinuses may
Sinusitis is the inflammation of the sinuses caused by a bacterial infection. Sometimes diagnosis may be problematic because the symptoms often mimic those of the common cold. Sinusitis is usually treated with antibiotics.
Sinusitis is the inflammation of the sinuses caused by a bacterial infection. Sometimes diagnosis may be problematic because the symptoms often mimic those of the common cold. Sinusitis is usually treated with antibiotics.
(Illustration by Electronic Illustrators Group.)
cause pain in patients with sinusitis, but it may not. A procedure called "sinus transillumination" may, or may not, also be helpful. Using a flashlight pressed up against the skin of the cheek, the practitioner will look in the patient's open mouth. When the sinuses are full of air (under normal conditions), the light will project through the sinus, and will be visible on the roof of the mouth as a lit-up, reddened area. When the sinuses are full of mucus, the light will be stopped. While this simple test can be helpful, it is certainly not a perfect way to diagnose or rule out the diagnosis of sinusitis.
X-ray pictures and CT scans of the sinuses are helpful for both acute and chronic sinusitis. People with chronic sinusitis should also be checked for allergies; and they may need a procedure with a scope to see if any kind of anatomic obstruction is causing their illness. For example, the septum (the cartilage which separates the two nasal cavities from each other) may be slightly displaced, called a deviated septum. This can result in chronic obstruction, setting the person up for the development of an infection.


Antibiotic medications are used to treat acute sinusitis. Suitable antibiotics include sulfa drugs, amoxicillin, and a variety of cephalosporins. These medications are usually given for about two weeks, but may be given for even longer periods of time. Decongestants, or the short-term use of decongestant nose sprays, can be useful. Acetaminophen and ibuprofen can decrease the pain and headache associated with sinusitis. Also, running a humidifier can prevent mucus within the nasal passages from drying out uncomfortably, and can help soothe any accompanying sore throat or cough.
Chronic sinusitis is often treated initially with antibiotics. Steroid nasal sprays may be used to decrease swelling in the nasal passages. If an anatomic reason is found for chronic sinusitis, it may need to be corrected with surgery. If a surgical procedure is necessary, samples are usually taken at the same time to allow identification of any organisms present which may be causing infection.
Fungal sinusitis will require surgery to clean out the sinuses. Then, a relatively long course of a very strong antifungal medication called amphotericin B is given through a needle in the vein (intravenously).

Alternative treatment

Chronic sinusitis is often associated with food allergies. An elimination/challenge diet is recommended to identify and eliminate allergenic foods. Irrigating the sinuses with a salt water solution is often recommended for sinusitis and allergies, in order to clear the nasal passages of mucus. Another solution for nasal lavage (washing) utilizes powdered goldenseal (Hydrastis canadensis). Other herbal treatments, taken internally, include a mixture made of eyebright (Euphrasia officinalis), goldenseal, yarrow (Achillea millefolium), horseradish, and ephedra (Ephedra sinica), or, when infection is present, a mixture made of echinacea (Echinacea spp.), wild indigo, and poke root (Phytolacca decandra-Americana).
Homeopathic practitioners find a number of remedies useful for treating sinusitis. Among those they recommend are: Arsenicum album, Kalium bichromium, Nux vomica, Mercurius iodatus, and Silica.
Acupuncture has been used to treat sinusitis, as have a variety of dietary supplements, including vitamins A, C, and E, and the mineral zinc. Contrast hydrotherapy (hot and cold compresses, alternating 3 minutes hot, 30 seconds cold, repeated 3 times always ending with cold) applied directly over the sinuses can relieve pressure and enhance healing. A direct inhalation of essential oils (2 drops of oil to 2 cups of water) using thyme, rosemary, and lavender can help open the sinuses and kill bacteria that cause infection.


Prognosis for sinus infections is usually excellent, although some individuals may find that they are particularly prone to contracting such infections after a cold. Fungal sinusitis, however, has a relatively high death rate.


Prevention involves the usual standards of good hygiene to cut down on the number of colds an individual catches. Avoiding exposure to cigarette smoke, identifying and treating allergies, and avoiding deep dives in swimming pools may help prevent sinus infections. During the winter, it is a good idea to use a humidifier. Dry nasal passages may crack, allowing bacteria to enter. When allergies are diagnosed, a number of nasal sprays are available to try to prevent inflammation within the nasal passageways, thus allowing the normal flow of mucus.



American Academy of Otolaryngology-Head and Neck Surgery, Inc. One Prince St., Alexandria VA 22314-3357. (703) 836-4444.

Key terms

Cilia — Tiny, hair-like projections from a cell. Within the respiratory tract, the cilia act to move mucus along, in an effort to continually flush out and clean the respiratory tract.
Sinus — An air-filled cavity.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.


inflammation of one or more of the paranasal sinuses, often occurring during an upper respiratory tract infection when infection in the nose spreads to the sinuses (sometimes encouraged by excessively strong blowing of the nose). It also may be a complication of tooth infection, allergy, or certain infectious diseases, such as pneumonia and measles. There are many other causes, including air pollution, diving and underwater swimming, sudden extremes of temperature, and structural defects of the nose that interfere with breathing, such as deviated septum.

As the mucous membranes of the sinus become inflamed and swollen, the openings that lead from each sinus into the nasal passages become partially or wholly blocked. The mucus that accumulates in the sealed-off sinus causes pressure on the sinus walls, resulting in discomfort, fever, pain, and difficult breathing.
Symptoms. The common symptoms of sinusitis are headache, usually located near the sinuses most involved, and nasal discharge. These may be accompanied by a slight rise in temperature, dizziness, and a general feeling of weakness and discomfort.

When sinusitis is suspected as the cause of such symptoms, the health care provider may use a light to evaluate the patency of the sinuses. A bright light is held against the forehead and cheeks to determine the amount of light transmitted through the sinuses in these areas. If a sinus is filled with fluid and inflamed it will transmit little or no light. Radiologic tests also are used to confirm a diagnosis of sinusitis and to locate the extent of involvement. Specialized techniques such as multiple x-ray exposures (polytomography) and computed tomography are sometimes used to pinpoint the nature and scope of a sinus disorder.

The American Academy of Pediatrics has developed clinical practice guidelines called Management of Sinusitis, applicable for anyone up to age 21. They note that imaging studies are not necessary to confirm a diagnosis of clinical sinusitis in children younger than age 6. They further recommend that CT scans be used only for those patients in whom surgery is a likely management strategy.
Treatment. Acute sinusitis usually responds to antibiotic therapy and increased drainage from the sinuses through the use of decongestants, which are applied locally in the form of nosedrops and also taken systemically. Inhalation of steam or warm moisturized air and local applications of heat encourage drainage and help relieve discomfort. Because of the severe pain associated with inflamed and swollen sinus membranes, potent analgesics may be needed for the first few days to provide relief and permit rest.

Chronic sinusitis often develops following a particularly resistant case of acute sinusitis. The mucous membranes in the sinuses thicken and normal drainage is obstructed. If medical management such as that described previously for acute sinusitis does not relieve the condition, surgical intervention may be necessary. In some cases, repair of a deviated nasal septum or removal of nasal polyps may be all that is necessary to eliminate the source of the problem. Others may need to have a new outlet created in the sinus to allow for drainage into the nose. More extensive surgery involves removal of the thickened membranous lining of the sinus or obliteration of the sinus itself in order to prevent refilling with purulent drainage.

Since sinusitis can lead to more serious infections in nearby tissues, such as the bones of the ear and mastoid or the brain, it is important that it be treated aggressively to eliminate infection. Though a change of climate can sometimes help in cases of chronic sinusitis, it rarely is a necessity. Creating a better indoor climate with such devices as air conditioners and humidifiers often is equally beneficial in reducing the number and severity of sinus attacks. Psychotherapy may be of help to some patients with disabling, chronic sinusitis because continual emotional strain is one of the factors that can intensify the symptoms.
ethmoid sinusitis inflammation of an ethmoid cell (ethmoid sinus); called also ethmoiditis.
maxillary sinusitis inflammation of a maxillary sinus; called also antritis.
sphenoid sinusitis inflammation of a sphenoid sinus; called also sphenoiditis.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


Inflammation of the mucous membrane of any sinus, especially the paranasal.
See also: rhinosinusitis.
[sinus + G. -itis, inflammation]
Farlex Partner Medical Dictionary © Farlex 2012


Inflammation of the sinuses or a sinus, especially in the nasal region.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


Infection and/or inflammation of paranasal sinuses, often caused by blocked drainage of fluid or purulent material, linked to swelling of nasal mucosa. 

Allergic rhinitis, viral respiratory infections, deviated nasal septum, other obstruction; swimming or immersion of head in water may allow water and bacteria to enter the sinus, causing irritation, infection and fluid-related pressure pain.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.


ENT Infection and/or inflammation of paranasal sinuses, often caused by blocked drainage of fluid or purulent material, linked to swelling of nasal mucosa Etiology Allergic rhinitis, viral respiratory infections, deviated nasal septum, other obstruction; swimming or immersion of head in water may allow water and bacteria to enter the sinus, causing irritation and infection, fluid-related pressure pain. See Allergic fungal sinusitis, Sinus.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


Inflammation of the lining membrane of any sinus, especially of one of the paranasal sinuses.
[sinus + G. -itis, inflammation]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


Inflammation of the mucous membrane linings of one or more bone cavities (SINUSES) of the face. This almost always results from infection. There is a feeling of fullness or pain in the forehead, cheeks or between the eyes, fever and general upset. Treatment may involve surgical drainage and antibiotics.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005


Inflammation of the lining membrane of any sinus, especially of one of the paranasal sinuses.
[sinus + G. -itis, inflammation]
Medical Dictionary for the Dental Professions © Farlex 2012

Patient discussion about sinusitis

Q. sinusitis How can I combat and cure sinusitis

A. Chronic sinusitis should be first diagnosed by an Ear Nose & Throat doctor. Antibiotics is usually the first choice of treatment, unless there is a known anatomical problem in the sinuses that requires surgical treatment. Acute sinusitis is treated with antibiotics. You can also use nasal sprays to ease congestion.

Q. SINUSITIS what are the causes,can you get it with a common cold?

A. sinusitis is an infection of the sinuses. an infection can be from all sort of things- bacteria, fungal, virus. the common cold usually caused by Rhinovirus, it can spread to the sinuses. it can also cause a blockage of the sinuses and then infection can occur.

Q. What Is the Treatment for Chronic Sinusitis? My daughter has been suffering from sinusitis for years now. We've tried all possible drugs but nothing really seems to help her anymore. Is there another option for treating chronic sinusitis?

A. For chronic or recurring sinusitis, referral to an otolaryngologist may be indicated for more specialist assessment and treatment, which may include nasal surgery. However, for most patients the surgical approach is not superior to appropriate medical treatment. Surgery should only be considered for those patients who do not experience sufficient relief from optimal medication. A relatively recent advance in the treatment of sinusitis is a type of surgery called FESS - functional endoscopic sinus surgery, whereby normal clearance from the sinuses is restored by removing the anatomical and pathological obstructive variations that predispose to sinusitis.

More discussions about sinusitis
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References in periodicals archive ?
Orbital cellulitis can arise from paranasal sinusitis; trauma to the eye; a retained foreign body in the orbit; ocular surgery; or contagious spread of infection from adjacent structures, such as dacryocystitis, dental abscesses, or preseptal cellulitis.
In patients with chronic paranasal sinusitis, improvement rates can be high following conservative therapy.
Uncommon anatomic variations in patients with chronic paranasal sinusitis. Otolaryngol Head Neck Surg 2005;132:221-5.
In the head and neck, Aspergillus species can cause otomycosis, allergic paranasal sinusitis, invasive paranasal sinusitis, and aspergilloma of the paranasal sinuses.